Per- and Polyfluoroalkyl Substances in Southern Ontario Drinking Water and Wastewater
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
The presence of 41 per- and polyfluorinated alkyl substances (PFAS) was investigated in raw and finished drinking water and in influent and effluent wastewater sampled from facilities in the Great Lakes Basin region of Southern Ontario, Canada (September–November 2023). Based on US Environmental Protection Agency Method 1633A, the method developed for analysis of these species demonstrates high sensitivity and recovery with limits of quantitation that range between 0.075 ng L –1 and 3.0 ng L –1 . Linear chain PFAS with carboxylic acid and sulfonic acid groups were detected in finished water from all drinking water treatment plants ( n = 6). Wastewater effluents ( n = 2) had PFAS concentrations approximately 1 order of magnitude higher than those in finished drinking water samples and included several fluorotelomers and ether-linked species. Across all sites, 13 of the 41 PFAS were detected in drinking water and 21 in wastewater. Average sum of 25 PFAS in finished drinking water ranged between 8.69 and 14.0 ng L –1, well below Health Canada’s objective of 30 ng L –1 . These results highlight the persistence of PFAS across treatment systems and suggest a potential feedback loop where wastewater effluents reintroduce PFAS into surface waters used as drinking water sources.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it